IBM graphene chip outperforms silicon

Emma Woollacott, 8th February 2010

IBM has developed the world's fastest graphene transistor, which outperforms traditional silicon.

The transistor has the highest cut-off frequency achieved so far for any graphene device - 100GHz, compared with a silicon record of 40GHz.

It was created using wafer-scale, epitaxially grown graphene, and much the same processing technology as that used in advanced silicon device fabrication.

"A key advantage of graphene lies in the very high speeds in which electrons propagate, which is essential for achieving high-speed, high-performance next generation transistors," said Dr TC Chen, vice president, Science and Technology at IBM Research.

"The breakthrough we are announcing demonstrates clearly that graphene can be utilized to produce high performance devices and integrated circuits."

IBM says it was able to create uniform and high-quality graphene wafers by thermal decomposition of a silicon carbide (SiC) substrate. The graphene transistor itself utilized a metal top-gate architecture and a novel gate insulator stack involving a polymer and a high dielectric constant oxide.

The gate length was modest, at 240 nanometers - and IBM says this leaves plenty of room to improve performance even further by scaling down the gate length.

IBM also experimented with graphene from different sources. These results came from devices based on graphene obtained from natural graphite, proving that high performance can be obtained from graphene of different origins.